Method of forming herring-bone gears.



N, A. GHRISTBNSENL METHOD 0F FOBKENG BIEEBBIIG BONE SEARS. APPLIOATIOEFILED JUEE 2B, 1904.

vN. A.`CHRISTENSEN. METHOD 0F FORMING HEBRING BONE GEARS. fAmfLIoATIoNfILED JUNE zo, 1904. 1

91 4,700. Patented Mar. 9, 1,909.

2 SHEETS-SHEET 2.

. UNITED s'rArns-ieannnfrlonnn.

NIELS A. CHRIS'IAENKSEN, OF MILWAUKEE, WISCONSIN.

METHOD OF FORMING H ERRING-BONE GEARS.

Specification of Letters Patent. i

Patented March 9, 1909.

Original application-filed October 19,-1899, Serial No. 734,091. Dividedand'this application filed June 5w,

' 1904. Serial No. 213,337.

To all whom it may concern:

Be it known that I, NrnLs A. CHmsTnNsnN,

' a citizen of the United States, residing at Milwaukee, in the countyof Milwaukee and State of Wisconsin, have invented certain new anduseful lm rovements in Methods of Forming Herringone Gears, of which thefollowing is a speciiication, reference being had to the accompanyingdrawing, forming a part thereof.

This invention relates to spiral gearing 'of the class shown anddescribed in my applica-- tion Serialhlo. 734,091, filed October 19,1899, of which my present application is a division.

The main .obj ect oi the invention is to simplify and improve theconstruction and operation of this class of gearing, and te facilitateand cheapen the manufacture thereof.

It consists in the method or process hereina'fter particularlydescribed, of constructing herringbone gears of sections havingreversely arranged spiral teeth and secured together side by side.

--in or rivetin them to ether; Fi 4 is a secg g g g tion indicatedy bythe line 4 4, Fig. 5, in a plane parallel with the axis of the gear, andF ig. 5 is a section indicated by the line 5 5, Fig. 4, in a plane-atright angles to the axis of the gear,.showing a iinished gearconstructed in accordance with my improved process and illustrating themanner and means of assembling and securing together the componentsections of the gear; and Fig. 6 is a view oi a portion of the face of afinished gear showing the arrangement and herringbone form of its teeth.

ln the construction of gearing in accordance with my' process, a numberof sections cast like or similar to that shown in Fig. l, are accuratelyturned true or faced on the sides per en'dicular or at right angles totheir axesan their hubs are bored. They are then secured together sideby sideI uponffa c Pw.

mandrel a, as shown in Fig. 2, and their peripheral faces are turned ina lathe. The sections having been turned true, are placed with the samemandrel in a milling or gear cutting machine and spiral teeth 'aresimultaneously cut therein, the teeth all running one' way, either rightor left, as shown in Fig.

2. ln other sections, secured together and turned true on a mandrel-asabove ex vlained, spiral teeth running in the opposite irection arecutin like manner.

Holes b, are drilled for bolting or riveting the component sections ofeach gear` together. ln order to form these holes so that they willexactly register with each other in the component sections of a earand-such sections when bolted or rivete together will be' exactlyconcentric and theirteeth *will have an exact predetermined relation toeach other, only a part of the holes, for example alternate holes, areprimarily drilled in each section, as shown in lFigs. 1 and 3. y

Two sections, one from each group or series, having teeth running inopposite directions and arranged with the holes t oi one section out ofregister with, preferably midway between, the holes in the othersection, and the teeth of each section in the exact desired relation tothe teeth of the other section, are clamped together in a centering rinor holder c, as shown in l5" 3. The bo t or 'rivet holes are then competed, the drill being guided by the holes previously formed in eachsection in drilling the additional holes in the other section. Eachsection thus serves as a jig for exactly'locating and drilling theregistering holes in the other section. ln this way the additional holesin each section are formed exactly in line with -the holes primarilyformed in the other section, so that when the two sections are bolted orriveted to ether they will be exactly concentric an the teeth of eachwill be in the exact desired relation to the teeth of the other. The twosections d and c thus pre# pared and drilled, `are then secured togethersideby side, by bolts or rivets f, as shown in Figs. 4 and 5, and formin effect an integral herringbone gear, the teeth ofwhose componentsections may be arranged to exactly meet each other at their innerends,l as shown 1n Fig. 6, or may be odset or staggered if de sired.AAfter the sections are thus assembled and secured together, the gear maybe centered b its periphery in a lathe and the bore of its 'hubiinishedconcentrically with its simultaneously in a number -ofassembledperiphery, and if desired, one or more liey vthe rivets pass arepreferably countersunk,

manner of performing theseveral operations -ed scope of the invention.

seats may be cut therein.

In the construction of gears of the lar er sizes, the sides of thesections are preferaly recessed, as shown in Figs. 1 and 5, to reducetheir weight, save materialand economize in the time and labor re uiredto face them. The outer ends of the oles through which as shown in Fig.4, so that when the rivets aref upset.therein, their ends will besubstantially iiush with the webs o r side faces of the gear. y

Herringbone gears constructed in accordance with m invention'ashereinbefore explained, can e made more rapidly and economically andtheir-teeth can be more acfcurately cut, than when they are madeaccordingto' the usual ractice, ina sin le piece. By my metho ofconstruction t e angles produced bythe meetingteeth of adjo' sectionsare sharp and perfectly forme ,a result that cannot be obtained bycutting angular teeth on a gearmade in one piece or having an integrallyformed rim. t isobvious also, that by cutting the teeth sections, in themanner hereinbefore vexplained, a gfreat saving ofl time, labor andl eXense ise ected.

arious cha es in the minor details of construction of t c gear and inthe order and hereinbefore described, maybe made Without departing fromthe principle and intendholes in the other, exactly Vlocating and form-Vand forming holes in the other section by the I claim:

1. The method Aof formingr herringbone gears, consisting in cuttingspiral or oblique teeth running in opposite directions in separatesections, primarily forming transverse holes in each section, te'morarily'securing said sections together in t e exact relation they areto `have `in the inished gear, with the holes in one section out ofregister with the in additional holes in each section bythe ho esprimarily formed in the other section, while the two sections aretemporarily held to ether in the exact desired. relation vto each ot er,and securing the sectionstogether bv means passing through the holesthusformed, substantially asl described.

2. The method of forming herringbonegears, in sections, consisting incutting spiral or oblique teeth running -in opposite directions in theseparate. sections', primarily forming transverseholes one section ofeach gear, vtemporarily securing the vsections together in the 'exactrelation they are to have in thefinished gear, exactly locating holesprimarily formed in the first4 section while the two sectionsare-temporarily held to etherili the exacty desired relation to each Iot er, and 'finallysecuring the sections toget-her by means passinthrough the holesthus formed, substantial v as described.

In Witness whereof, I eretolaiiig( my sig# nature in presence of twoWitnesses.

i -NIELS A. CHRISTENSEN. Witnesses:

JNO, DADMUN, Cms. L. Goss.

